The actual dashboards are made up of widgets which are typically self-contained reports based on your analytics data. There are some exceptions to this, such as widgets containing news feeds and social media integrations.
Matomo comes with approximately 100 widgets by default, and they are all displayed in an interactive card format. Widgets can also be added via plugins if you are using Matomo On-Premise or Matomo for WordPress. The screenshot below shows a typical dashboard with several different styles of widget within the white boxes. These provide a high-level overview of key stats for your website.